Apparatus used for automating development and printing of photographic materials include a widely known type of apparatus generally referred to as a "minilab" and similar equipment. By using these automated devices, retail and wholesale film developers develop photographic film and process prints in a well-controlled process environment that assures quality prints for their customers. Minilab types range from small, low-volume retail units to medium- and high-volume equipment used by major photo retailers.
In addition to minilab systems, this invention also relates to other types of photoprocessing equipment. These can include high-volume photoprocessing systems such as the "Gretag CLAS 35 System" manufactured by Gretag AG located in Regensdorf, Switzerland that makes photographic prints from negatives using optical exposure methods. Additionally, this invention relates to other high-volume photoprocessing systems that use digital printing technologies instead of traditional optical methods for exposing photosensitive paper. As used herein, the terminology "photoprocessing", also known as "photofinishing", includes but is not limited to the entire process whereby a consumer image source (e.g., exposed roll of film) is printed onto a viewable medium such as photographic paper, with steps which may include film developing, printing and paper processing. Digital technologies employed for exposure of photosensitive paper in photoprocessing applications include, but are not limited to the following, which supply exposure energy in digitized form:
Laser printing, which typically employs one or more lasers; PA1 CRT printing, which employs one or more scanning electron beams; PA1 L.E.D. printing, which employs one or more focused Light-Emitting Diodes. PA1 Manual entry via keyboard. Manual entry of batch number data is error-prone and could be easily ignored by a hurried technician. Manual entry does not adequately solve problems of continuously tracking the amount of consumable used. For example, paper could be replaced temporarily with a different roll, or chemicals might be removed during cleaning. PA1 Bar code labeling. Providing a bar code on consumable packaging is another option, but requires multiple readers disposed within the apparatus, one for each consumable package. Light-sensitivity restricts the practical uses of bar-code reading for photographic paper. PA1 Embedded trace patterns. As disclosed in International Publication Number WO 98/52762 (Purcell, et al.), specific trace patterns could be used to identify a consumable type. However, this type of data encoding is fairly inflexible with respect to data storage and provides very little information. PA1 Memory circuit. U.S. Pat. No. 5,610,635 (Murray, et al.) discloses enclosing a read/write memory circuit as part of an ink jet cartridge. Using this arrangement, information can be accessed from the cartridge as well as written to the cartridge. Thus, for example, a cartridge can be coded with a print count that gives an indication of how much ink is left in the device. Use of the memory circuit as disclosed in U.S. Pat. No. 5,610,635 could have advantages for use with photoprocessing consumables; however, the need for added interconnect and support circuitry makes use of such a circuit somewhat expensive and places demands on connector hardware reliability.
In addition to photoprocessing systems, this invention also relates to digital printers that are not directly used for photoprocessing, but expose images onto photosensitive paper. One such system is the "KODAK LED DIGITAL COLOR PRINTER 20P" manufactured by Eastman Kodak Company located in Rochester N.Y. This printer creates, on photosensitive, silver-halide-based paper, high-quality color images from a digital image source.
Other related equipment to which the present invention may be applied also includes apparatus configured to develop film negatives or slides or apparatus configured to expose prints onto photosensitive paper.
As the above description indicates, the present invention has application to an imaging apparatus that exposes photosensitive paper or consumes photoprocessing chemicals. The description that follows describes the present invention primarily as used with minilab apparatus; however, it is to be understood that the methods disclosed in this specification can be applied more broadly to include the above recited other types of photoprocessing apparatus, printers, developers, and other apparatus.
For printing, minilab operation is fairly straightforward and follows the general sequence described here. The minilab exposes the photographic image from developed film onto photosensitive paper. (It should be noted, from the above discussion, that optical exposure is only one exposure method. Digital minilabs can use other means for providing controlled exposure energy, such as lasers, CRT writers, or LEDs.) Then, the apparatus routes the exposed paper through a sequence of chemical baths in which the image is developed, fixed, and stabilized onto the paper. The consumable items of interest for this invention are both the photosensitive paper that is fed into the minilab and the photoprocessing chemicals that are mixed with water in the chemical baths to provide proper solutions for developing a print or negative.
Other non-minilab apparatus noted above perform, with variations, one or more similar operations as described for minilabs. For example, a digital printer as described above may perform only an exposure operation, whereby the photosensitive paper is exposed, to be subsequently developed on other equipment. For such equipment, processing takes place by feeding new, unexposed photosensitive paper from a feed roll, exposing the paper, then wrapping the exposed paper about a take-up roll, for development at a later time.
Necessarily, the consumables (photosensitive paper and photoprocessing chemicals) used in the minilab are manufactured to high quality standards, with sensitometry and other variables maintained to within tight tolerances. Included in the tolerance considerations are margins for unknown variables at minilab sites. That is, worst-case conditions must be assumed when assessing consumables quality, because the manufacturer cannot know the specific type of minilab system into which the consumable will be loaded. Similarly, the manufacturer cannot predict batch interactions where, for example, a specific batch of photosensitive paper manufactured today could be processed using a specific batch of chemicals manufactured several months previously. Batch-to-batch variations are known to exist, particularly with color film, photosensitive color paper, and chemicals. Today, manufacturers are constrained to tight tolerances and higher costs due, in part, to such worst-case requirements. At the same time, a significant amount of testing is routinely performed on each batch of consumable manufactured, both for paper and for photoprocessing chemicals. Detailed information about each batch, if it were available, could be used to optimize the performance of equipment using these consumables.
The owner of the minilab or other photoprocessing apparatus pays close attention to image quality and is encouraged to follow a set of recommended practices for cleanliness, storage, and stock rotation for these consumables. In general, the minilab equipment is designed to make it easy for an operator to load the correct paper for the prints being processed and to provide the photoprocessing chemicals in the proper concentrations.
Notably, because of economic and environmental concerns, it is advantageous for manufacturers of minilabs to provide a high degree of control over the processing operation, including providing as much information as is necessary about process variables in order to obtain the best quality economically and with minimum waste. To facilitate this tight control, many minilabs include front-end computers that act as control processors and provide various sensing and reporting capabilities for the minilab operator. Among example systems that provide this capability are the "Noritsu QSS-2xxx" series minilabs manufactured by Noritsu Koki Company, Ltd. Located in Wakayama, Japan.
Of particular importance for this invention are the methods by which consumable paper and photoprocessing chemicals are packaged. Photosensitive paper for minilab equipment is typically provided in roll form, with the paper provided in specific roll widths, wound around a core, typically of cardboard. The minilab technician preloads the photosensitive paper roll into a light-tight canister, then installs the canister onto the minilab apparatus. With some types of minilabs (for example, the "Noritsu QSS/SM-2xxx" series), the operator also needs to preset a number of mechanical or magnetic switches on the cartridge in order to indicate to the apparatus what width of paper is loaded into the canister. Or, the operator may be required to enter the width manually on a computer screen or other control console. To track information on roll widths and canister contents, operators use a number of schemes, including manually pasting a label onto the loaded canister.
There are a number of alternative methods for loading photoprocessing chemicals in the minilab. For some machines, particularly at large-scale photoprocessing sites, technicians manually mix each batch of each needed chemical type, combining a pre-measured amount of concentrated chemical and water in a tank. Other systems, however, employ packaged chemicals in some form, whether liquid or pelletized. Here, the packaged chemical is installed within the minilab itself. For such systems, the minilab equipment itself performs the pumping and mixing operations, pumping from the packaged chemical (or extracting a pellet) as needed to maintain bath solutions at the proper concentrations.
"KODAK EKTACOLOR SM Chemicals" manufactured by the Eastman Kodak Company are one example of liquid chemical especially packaged for use in minilab apparatus. The overall method of packaging for concentrated photoprocessing chemicals in this series of products is as described in U.S. Pat. No. 5,694,991 (Harris et al.)
U.S. Pat. No. 5,754,915 (Masuda, et al.) discloses an alternative pelletized system for photoprocessing chemicals. Here, the minilab technician loads a container of pellets onto the machine, with the pellets organized into individual compartments for each chemical type.
It would be advantageous for a minilab to be able to access information automatically from the consumable media itself. Data such as batch number, date of manufacture, emulsion type (for photosensitive paper) and other application-specific information could be used to facilitate handling and processing of the consumable paper or chemical.
As noted above, the consumables manufactured for minilab processing are tested and characterized for performance within certain tolerances. Information on each batch could be used by the minilab's computer processor to optimize system performance. Conventional methods for entering identifying batch information, however, present significant drawbacks. The following methods are employed with various photoprocessing apparatus:
International Publication Number WO 98/52762 discloses an inkjet printer that uses, among a number of other sensors for environmental conditions and consumables status, an RF ID tag device as a means for identifying the type of paper that is loaded in an inkjet printer. This approach offers the advantage of contactless communication with a read/write memory that is added to the inkjet roll. This implementation uses only a single RF ID tag component, limited to the receiver medium in an inkjet printer. In limited inkjet printer environments, only a small amount of information is needed about the media, as is disclosed in WO 98/52762. In the implementation disclosed in WO 98/52762, moreover, introduction of new media could require an update to existing components, for example, to upgrade firmware circuitry if batch information indicated that alternate processing was required for the new media.
Additionally, implementing solutions such as are disclosed in U.S. Patent No. 5,610,635 would require substantial retrofit for existing apparatus in the field.
It can be seen from the above background description that there is a need for an automated method for obtaining and maintaining detailed data from photographic paper and photoprocessing chemicals used in an automated photoprocessing apparatus.